WESEN” 
FORNERIS, V.', CESARINI, C.', BONOFIGLIO, L.?, COLOMBO, F.?, NOVELLINO, A.? 
ICNR, Italy; 7ETT SpA, Italy 
INTRODUCTION 
Dissemination Units (DU) are important components of the 
Copernicus Marine Environment Monitoring Service 
(CMEMS), being in charge of the dissemination of products 
elaborated by Production Centres (PC; MFCs and TACs) 
making data available to users by means of severaı 
ınterfaces such as: File Transfer Protocol (FTP), Web Map 
Service (WMS), Subsetter (MOTU) and Direct Get File (DGF) 
Juring Copernicus Marine Service Phase 1, there were 
multiple DUs, each part from different PCs (Figure 1). While 
providing more flexibility toward producer's data (DU 
adapted for providing specific data), the overall Service 
was unbalanced as some DUs proved to be less stable than 
others. Moreover, having multiple/different access points, 
above all for operative/automatic/m2m (machine-to- 
machine) procedures, increased the overall complexity for 
users accessing different portions of Copernicus Marine 
Service Catalogue. 
At the beginning of Phase 2, Copernicus Marine Service 
Improved its service by changing this distributed approach 
in favour of a consolidated approach. The new DUs (one per 
Near Real Time/Analysis data, one per Multiyear data) 
main missions were (and are still) to: 
„set up & maintain infrastructures for integration and 
operations, 
collect products from Production Units (PUs) & 
disseminate them to users, and 
-ensure & monitor operations related to the collectior 
& dissemination. 
Central Web portal | Catalog |CAS| Transaction-Accounting 
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zure 1: Copernicus Marine Service phase‘ DUfs) architecture